Wood composites on the bases of a cured, i.e., crosslinked, resin which adheres the wood parts to one another exist for many years and form a mature market. Examples of such composites are plywood and particle board. In the manufacture of the wood compositions, curing is usually effected by applying a heat treatment. Examples of curable resins that are widely used in the manufacture of wood composites include urea formaldehyde resins and phenol formaldehyde resins. Although these resins are being used, the wood composites prepared therewith have an unsatisfactory performance in important market segments, viz., those wherein there is a demand for a high impact resistance or a demand for a good dimensional stability of the composite in the presence of moisture.
The present invention provides improved wood composites which are based, as regards the binder, on a copolymer of carbon monoxide and an olefinically unsaturated compound and a curing agent. The composites of the present invention have improved impact resistance/strength balance and improved dimensional stability compared to wood composites based on prior art binders. They are also tougher and more homogeneous. The binder may be applied at a surprisingly low amounts.
Moreover, when the binder is also applied at the outer surface of the composite a composite with a soft "hand feel" is obtained after curing. This constitutes an advantage over wood composites which have a conventional binder as a surface coating. A soft hand feel implies that the surface feels as if it has had a polish treatment.